So this should work on any bash-shell running system with Python
installed. Obviously this works for any site with images, but you
can't go wrong with APOD.
I've only tested it on ubuntu 15.04. If you try it and
it breaks, let me know!
Clone this repository to a local directory on your computer.
In run.sh, be sure to source whatever your relevant shell login profile is for the
source call.
Modify what I put in as absolute paths to whatever is appropriate on your system.
In the python call, make sure to use the absolute path of your python installation.
The real trick in this is getting cron the correct environment variables. To set a desktop
background in gnome with gsettings, that variable is DBUS_SESSION_BUS_ADDRESS. See the
relevant stack exchange
description.
This script does the bulk lifting, downloading the image and writing out the caption
in a text file to your desktop.
It outputs a gsettings command that with appropriate nudging, run.sh executes.
chmod +x both the python and the shell scripts.
Your cron file (crontab -e) should include:
SHELL=/bin/bash
13 2 * * * /home/lgbouma/Dropbox/apod_wallpaper/run.sh
where the time is whenever every 24 hours you want the freshest new astronomy pictures on the block!